The coprecipitation of Cd, Co and Eu from seawater onto ferric hydroxide was studied, using the radioactive tracers <sup>109</sup>Cd, <sup>60</sup>Co and <sup>152-154</sup>Eu, as a function of the pH, the concentration of the collector iron, the concentration of the metal spike and the aging of the internally formed precipitate. For preconcentration purpose, a pH 9 and a 35 ppm iron concentration appeared to be suitable. At pH 8, the natural pH of seawater, the distribution coefficients for Cd, Co and Eu are 10<sup>4.5</sup>, 10<sup>5</sup> and 10<sup>7</sup>, respectively. |